JAMB Mathematics 2019 Paper

$M \propto N$ ; $M \propto \frac{1}{\sqrt{P}}$.

$\therefore M \propto \frac{N}{\sqrt{P}}$

$M = \frac{kN}{\sqrt{P}}$

when M = 3, N = 5 and P = 25;

$3 = \frac{5k}{\sqrt{25}}$

$k = 3$

$M = \frac{3N}{\sqrt{P}}$

when M = 2 and N = 6,

$2 = \frac{3(6)}{\sqrt{P}} \implies \sqrt{P} = \frac{18}{2}$

$\sqrt{P} = 9 \implies P = 9^2$

P = 81